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4 4-5. Using the driving support system
Driving
GS450h_300h_OM_OM30D53E_(EE)
CAUTION
To avoid inadvertent dynamic radar cruise control with full-speed range
activation
Switch the cruise control off using the “ON/OFF” button when not in use.
Situations unsuitable for dynamic radar cruise control with full-speed range
Do not use dynamic radar cruise control with full-speed range in any of the
following situations.
Doing so may result in inappropriate speed control and could cause an acci-
dent resulting in death or serious injury.
In heavy traffic
On roads with sharp bends
On winding roads
On slippery roads, such as those covered with rain, ice or snow
On steep downhills, or where there are sudden changes between sharp up
and down gradients
Vehicle speed may exceed the set speed when driving down a steep hill.
At entrances to expressways
When weather conditions are bad enough that they may prevent the sen-
sors from functioning correctly (fog, snow, sandstorm, heavy rain, etc.)
When an approach warning buzzer is heard often
When your vehicle is towing a trailer or during emergency towing
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3364-5. Using the driving support system
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CAUTION
When the radar sensor may not be correctly detecting the vehicle ahead
Apply the brakes as necessary when any of the following types of vehicles
are in front of you.
As the sensor may not be able to correctly detect these types of vehicles, the
approach warning (P. 308) will not be activated, and a fatal or serious
accident may result.
Vehicles that cut in suddenly
Vehicles traveling at low speeds
Vehicles that are not moving
Vehicles with small rear ends (trailers with no load on board etc.)
Motorcycles traveling in the same lane
Conditions under which the vehicle-to-vehicle distance control may not
function correctly
Apply the brakes as necessary in the following conditions as the radar sen-
sor may not be able to correctly detect vehicles ahead, and a fatal or serious
accident may result:
When water or snow thrown up by the surrounding vehicles hinders the
functioning of the radar sensor
When your vehicle is pointing upwards (caused by a heavy load in the
trunk etc.)
When the road curves or when the lanes are narrow
When steering wheel operation or your position in the lane is unstable
When the vehicle ahead of you decelerates suddenly
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3394-5. Using the driving support system
4
Driving
GS450h_300h_OM_OM30D53E_(EE)
Lane departure warning function
If the system judges that the vehicle may deviate from its lane, it
alerts the driver using beeping, screen displays and a sensory
warning
* given via the steering wheel.
*: A slight steering torque is applied for a short period of time in the direc-
tion of the center of the lane.
Lane keeping assist function
• This function will be active when the vehicle-to-vehicle dis-
tance control mode of the cruise control (P. 302) is set with
vehicle speed above approximately 72 km/h (45 mph) and
while the lane departure warning function is active.
• When the lane keeping assist function is active, a slight steer-
ing torque will be applied, to help the driver maintain the vehi-
cle inside the lane.
The lane keeping assist function will be temporarily canceled if the
steering wheel is not operated, or if you continue driving with your
hands lightly touching the steering wheel. (P. 343)
Functions included in the LKA
1
2
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3414-5. Using the driving support system
4
Driving
GS450h_300h_OM_OM30D53E_(EE)
Lane departure warning function
When the vehicle speed is approximately 48 km/h (30 mph) or
more
When the lane width is more than approximately 3.0 m (9.8
ft.)
When driving on a straight road or through a curve with a
radius of more than approximately 120 m (394 ft.)
Lane keeping assist function
When the vehicle speed is between approximately 72 and 180 km/
h (45 and 112 mph)
When the vehicle-to-vehicle distance mode of the radar cruise
control is on, and the set vehicle speed is approximately 72
km/h (45 mph) or more (the function will not operate when the
radar cruise control is in set speed mode)
When the lane width is between approximately 3.0 and 4.0 m
(9.8 and 13.1 ft.)
When driving on a straight road or through a curve with a
radius of more than approximately 200 m (656 ft.)
Operating conditions for each function
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3424-5. Using the driving support system
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When the LKA system is on, the lane line display and steering
wheel display are shown.
Lane keeping assist function
operation indication
Steering wheel displayed:
Indicates that the function is cur-
rently operating. (If the lane depar-
ture warning operates at this time,
the steering wheel flashes orange.)
Steering wheel not displayed:
Indicates that the function is not
currently operating. (When the
lane keeping assist function is can-
celed, the buzzer will beep twice.)
Dynamic radar cruise control
display
Lane departure warning func-
tion indication (when the
inside of the white line is
white):
The function has recognized lane
markers. (If the lane departure
warning operates at this time, the
lines flash orange.)
Lane departure warning func-
tion indication (when the
inside of the white line is
black):
A lane marker is not recognized by
the system, or the LKA system
functions are temporarily canceled.
Indication on the multi-information display
1
2
3
4
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3434-5. Using the driving support system
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Driving
GS450h_300h_OM_OM30D53E_(EE)
Temporary cancelation of the LKA system functions
If any of the following occurs, the LKA system functions will be temporarily
canceled. The functions will resume after the necessary operating conditions
have returned.
The steering wheel is turned as far as necessary to cause the vehicle to
change lanes.
When the system detects no-handed driving. (The lane keeping assist func-
tion will be temporarily canceled, but the lane departure warning function
will continue.)
The turn signal lever is operated.
The vehicle speed deviates from the operating range of the LKA system
functions. (The buzzer will beep twice when the lane keeping assist func-
tion is being canceled.)
When the lane lines cannot be recognized while driving. (The buzzer will
beep twice when the lane keeping assist function is being canceled.)
The wiper switch is set on high speed mode or is set on AUTO mode with
wipers operating at high speed. (The lane keeping assist function will be
temporarily canceled, but the lane departure warning function will con-
tinue.)
If the vehicle crosses a line for approximately half a minute or more. (The
lane keeping assist function will be temporarily canceled, but the lane
departure warning function will continue.)
When the lane departure warning function is activated.
The lane departure warning function will not operate again for a several
seconds after it has been activated, even if the vehicle leaves the lane again.
The lane departure warning
It may be difficult to feel the sensory warning depending on the road condi-
tions.
No-handed driving warning
If the steering wheel is not operated for approximately 15 seconds on a
straight road or approximately 5 seconds on a curve, the buzzer will beep
twice, indicators on the multi-information display will flash, and the lane
keeping assist function will be temporarily canceled. If you drive the vehicle
with your hands lightly touching the steering wheel, this may also be
detected as no-handed driving.
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3444-5. Using the driving support system
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After the vehicle has been parked in the sun
The LKA system functions may not be available and a warning message
(P. 854) will be displayed for a while after driving has started. In such
cases, turn the LKA system off and turn it on again after normal temperature
returns. When the temperature in the cabin decreases and the temperature
around the camera sensor (P. 338) becomes suitable for its operation, the
functions will begin to operate.
If there are lane markers on only one side of the vehicle
The lane keeping assist function will not operate. Also, the lane departure
warning will not operate for the side on which lane markers could not be rec-
ognized.
Conditions in which the function may not operate correctly
In the following conditions, the LKA system functions may not operate, or it
may not be possible to ensure adequate performance. Also, the camera sensor
may be unable to recognize lane lines causing the lane departure warning
function to operate incorrectly, or the lane keeping assist function may not
operate properly. However, this does not indicate a malfunction.
When driving through an area with no lane markers, such as a tollbooth, a
crossing or before a ticket checkpoint
When driving on a sharp curve
When lanes are extremely narrow or extremely wide
When the vehicle leans to one side an unusual amount due to a heavy load
or improper tire inflation pressure
When the following distance between your vehicle and the vehicle ahead is
extremely short
When the lane markers are yellow (These may be more difficult for the sys-
tem to recognize compared to white markers.)
When the lane markers are broken, “Raised pavement marker” or stones
When lane markers are obscured or partially obscured by sand, dirt, etc.
When there are shadows on the road running parallel with lane markers, or
if a shadow covers the lane markers
When driving on a particularly bright road surface, such as concrete
When driving on a road surface that is bright due to reflected light
When driving in a location where the light level changes rapidly, such as the
entrance to or exit from a tunnel
When sunlight or the headlights of oncoming vehicles are shining directly
into the camera lens
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Driving
GS450h_300h_OM_OM30D53E_(EE)
When driving on roads that are branching or merging
When driving on a road surface that is wet due to rain, previous rainfall,
standing water, etc.
When the vehicle experiences strong up-and-down motion such as when
driving on an extremely rough road or on a seam in the pavement
When headlight brightness at nighttime is reduced due to dirt on the lenses,
or when the headlights are misaligned
When driving with a strong crosswind
When driving on winding roads or roads that are uneven
When driving on rough or unpaved roads
When changing the tires
Depending on the tires used, sufficient performance may not be maintain-
able.
Warning messages for LKA
Warning messages are used to indicate a system malfunction or to inform the
driver of the need for caution while driving. (P. 842, 854)
CAUTION
Before using the LKA system
Do not rely solely on the LKA system. The LKA system does not drive the
vehicle automatically, nor does it reduce the amount of care you need to
take. As such, the driver must always assume full responsibility for under-
standing his/her surroundings, for operating the steering wheel to correct
the driving line, and for driving safely.
Inappropriate or negligent driving could lead to an accident.
To avoid operating the LKA by mistake
Switch the LKA off using the “LKA” switch when not in use.